1. Field of the Invention
The present invention relates to an exhaust pipe structure for vehicles such as motorcycles.
2. Description of Background Art
An exhaust pipe structure is known wherein an exhaust chamber is provided somewhere along the exhaust pipe extending in the front-to-rear direction of vehicle, with an exhaust-gas inlet formed at the front side of the exhaust chamber and an exhaust-gas outlet formed at the rear side. See, for example, Japanese Utility Model Application Laid-Open No. Sho 60-18839.
In the above-mentioned exhaust pipe structure, for the purpose of making a change in engine characteristics (particularly, engine power) depends linearly on the throttle opening angle. Possible ways of achieving this object include elongating the exhaust pipe, and increasing the volume of the exhaust chamber. These measures, however, accompany an increase in the length of the exhaust pipe as a whole in the front-to-rear direction, and an enlargement of the dimension of the exhaust chamber, so that it is sometimes difficult to secure a space for placing the elongated exhaust pipe or the enlarged exhaust chamber.